The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 07, 1981
Filed:
Jan. 03, 1980
Applicant:
Inventors:
Kazys Sekmakas, Palatine, IL (US);
Thomas H Plaisance, Wilmette, IL (US);
Assignee:
DeSoto, Inc., Des Plaines, IL (US);
Primary Examiner:
Int. Cl.
CPC ...
C08G / ;
U.S. Cl.
CPC ...
528145 ; 204 / ; 2041 / ; 260 293 ; 525504 ; 528147 ; 528153 ; 568608 ; 568609 ;
Abstract
A bisphenol is reacted with formaldehyde in solution in alcohol in the presence of an alkali metal hydroxide, preferably at a pH of from 7-10, to provide a polymethylol derivative. Nitric acid is then added to precipitate the hydroxide and an excess is preferably used to provide an acid pH, preferably pH 1-3, and the acidic mixture is heat reacted to remove water of etherification. The nitric acid catalyst is then precipitated with alkali metal hydroxide to enable easy removal of both acid and alkali as an insoluble salt.